Have fluctuating body temperature. Blood test normal. Is this related to thyroid problem?

Hi Dr Christensen I have been feeling unwell for several months, and have the sympto
ms of Hypothyrodism, I have had several blood tests and they are all normal.
I have taken my temperature four times per day for many weeks, and it
fluctuates between 34 and 36 but never gets up to 37
Usually I feel better when my temperature is higher.
My condition does not appear to be getting worse, but most days I feel that I have mild flu like
symptoms, I am 68 slim and very fit for my age, have always had regular exercise.
If you could help, i would be very grateful
XXXXXXX

Hello,Thanks for posting your query.Considering your history the most likely possibilities in your case would be 1.a vitamin B 12 or Vitamin D3 deficiency.2 Hormonal disturbance like low testosterone levels.3. Low BMRSince you have been evaluated by a doctor and investigated the chances are less that they might have missed any major pathology. I would advise you first take some B complex supplements to watch for any relief.If problem persists then get yourself evaluated by an endocrinologist for proper diagnosis. Please do not worry, avoid stress, smoking, caffeine and alcohol to have better relief.Also try to include a mild exercise schedule like yoga in your daily lifestyle.I hope this answers your query. In case you have additional questions or doubts, you can forward them to me, and I shall be glad to help you out.Please accept my answer in case you do not have further queries.Wishing you good health.Regards.Dr. Praveen Tayal.